Carbureter.



PATENTED SEPT. 10, 1907.

WE R. PARK. GARBURETER.

APPT-NATION FILED FEB. 23, 1906.`

5 SHEETS-SHEET 1.

WITNEEEEE v PATENTED SEPT. l0, 190'7.'4 W. LR. PARK.

CARBURETER,

APPLICATION FILED 513.23, 19'06.

5 SHEETS-SHEET 2.

WIFI-NEE 5 E E .BATENTED SEPT. 10, 1907.

W. R. PARK. GARBURETER.

APPLICATION PIL'BD PEB. 23, 1906.

5 SHEETS-SHEET 3.

,MA1-NEE. '5E E:

PAT'ENTED SEPT. 10, 1907'.l

5 SHEETS-SHEET 4K W. R. PARK. CARBURBTER. APPLioATIoN FILED rma. 2a,190e.

iiiii :mmmllll d' llllll PATENTED SEPT. 10, 1907..

W. R. PARK.

A GARBURETER. APPLIoA-TION Pimp 1113.23, 190s.

5 SHEETS-SHEET 5.

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WTNESEEe-E;

gine. matic pressure and determination of the proportion of lshowing-thefuel strainer in perspective. t

PATENT. essieu.

UNITED STATES WILLIAM PARK, OF TAUNTON, MASSACHUSETTS. l

y. ('JAIRIBURIETER..l

specification of Lettis Patent.

Patented sept. 1o, 1907.

To all whom it' may concern:

Be it known that I, WILLIAM R. PARK, a citizen of the United States, anda resident of Taunton, in the county of Bristol and State ofMassachusetts, have invented new and useful Improvements in Carbureters,o'fwhichthe following is a specification.

My invention relates to carbureters for internal combustionengines whichemploy a fuel mixture of air and volatilizedhydrocarbon, and consists incertain improvements in structure whereof the object is to maintain acorrect proportion of the fuel ingredients delivered to the engine underchanging conditions and to accomplishthis result by an automaticregulation of pneumatic pressures without the aid of complicatedmechanical self-adjustingdevices. I attain these objects by soconstructing the air and gaseous-mixture passages of the carbureter thatno matter what the position ofthe throttling valves may be, `thepneumatic pressure in the mixing chamber, which contains the liquid fuelsprayingnozzle, is very nearly constant, its variation from the constantbeing so slight vthat for all practical purposes the approximation toconstancy of pneumaticpressure may be considered perfect. Byestablishing constant pneumatic pressure at the spray nozzle which isthe criticall point in the apparatus, Iam enabled to control withcertainty the amount of liquid fuel admitted to the' air passages of thecarburetor andv can, therefore, establish'either a ,constant or aregularly graded proportion of liquid hydrocarbon to air in determiningl the mixture which shall pass to the cylinders of the en- Moreover,this maintenance of constant pneuhydrocarbon fuel to air, is secured inmy carburetor Without the employment of delicate movingparts and withonly that sure and simple adjustment which may be secured by the meremovement of valves.

In the drawings hereto annexed which illustrato embodiments 'of myinvention and improvements- Figure l is atop plan view of the casing ofa carburetor with the covers and valve operating parts thereof removed;rFig. 2` is al top plan view of the carburetor in its en-` tirety;. Fig.3 is a vertical section of Fig. 2 through tllc line 3 3; Fig. 4 is avertical section of Fig. 2 along thc line 4--fl; Fig. 5 isa verticalsection of .Figi 2 along the line 5-5; Fig. 6 is a vertical elevation ofthe air and mixture throttle valve removed from the casing; Fig. 7 is across section of Fig; 6 along the line 7 7; Fig. 8 is a crosssection ofFig. 7 along the line 8-8; Fig. 9 is an elevation of the' carburetoras-it would appear when viewed from a point at ,the upper right handside' of Fig. 2;` Fig. 10 is a sectional view ofthe air and mixturetlirottle'viilvein its upper and lower parts with the airgand mixturepassages wide open; Fig. l1 is a similar visw of said throttle valvcfandadjacentparts when the throttle is closed; and -Fig. l2 isa detail,

The carbureter casing is as usual cast in a single piece of brass,bronze or other incorrodible metal and has the float chamber A, theliquid fuel valve chamber B, the mixing chamber D and the throttle valvechamber E. Within the float chamber A there is mounted in bearings, soas to slide vertically in the usual way, the float Af which carries andcontrols the valve A3 which seats in the pipe union A4 to whichgasolene, alcohol or other volatile liquid fuel is delivered through thepipe A5. The chamber A communicates with the interior of the chamber B,the channelA being provided for the purpose of conducting the liquidfuel from one chamber to the other. The volatile liquid hydrocarbonsupplied by the float controlled valve passes through the lower portionB of the chamber B to the liquid level indicated by linex-x of Fig. 3,which is the level predetermined by the adjustment of the float. Thislevel may obviously be varied by adjustment as variations in the l'uelquality may indicate. The sinuous path the fuel is thus compellodto passprovides a safe seal and prevents the possible entrance ol air intotheffuelvcurrent.' This supply of liquid fuel is controlled by the valveB3 which seats over and controls the fuel passage B2.

The conduit through which the liquid hydrocarbon fuelA flows from thewell B to the regulating valve B3 is the' pipe I which is reduced in itsexternal diameter at I The draner plug B5 has mounted upon it orpreierably as a part integral with it, the sleeve K perforated with anumber of holes k. Around the outside of the sleeve l( there is wrappedand soldered a' fine wire screen K/ which serves to arrest any particlesof foreign matter which may have entered the carburetor. The

upper end of the sleeve K fitssnugly upon the tube I whereof the reducedportion I. occupies the space within the said sleeve. Whenever it isdesired to inspect the strainer or to clean it, it may be removed bysimply unscrcwiug the plug B5. The valve B is secured to or is aninlogt-al part of a screw threaded stem B* which tirrnaiifa'suitablythreaded standard b4 which is cast as an'iiucgral portion of thecarburetor casing. The mixing chamber of the carburet-er Vis shown incross section in Fig. 5. Across the upper part of this mixing chamberextends the tubular bridge D', the interior bore d of which communicateswith the valve controlled fuel .passage B". The tubular bridge D isbored through vertically at DI so as to admit the-spraying stem D5whereof the head D passes into the vertical bore D3 so as to form withits walls au annular spraying orifice or nozzle. The stem D5 is securedto or formed integral with the threaded -pl ug D4 which is inserted andscrewed to its seat from above. Below the spraying orifice formed by thehead D and vertical bore. D, ,there is formed' the downwardly tapering`combining tube D into and through which the mixture of air andvol-.itilized hydrocarbon is drawn on its w-.ty to the engine cylinders.The double valve E El is mounted and lll) fitted to turn .in thevertical cylindrical valve chamber E. The double valvev is shown as madein two parts which are secured together'. It might, however, be made asone integral piece with the two distinct valve portions above and below.ln the upper portion E there arel formed the openings ef, ci whichcommunicate respectively with the air inlet Ff and the mixing chamber D,and the lower valve section E2 has ports or openings e3, e? whichcommunicate respectively with the mixture outlet I"` and with thecombining tube D` of the mixing chamber D. The stem E3 has secured to itthe crank arm E which, by means of a. suitable connection ate4 may becontrolled'by the throttle operating-devices in the usual Way.

The air inlet F, the chamber in the npper'part of the valve, E, mixingchamber D, the chamber in the lower part of the valve, E2, the outlet F2constitute collectively a gas conduit into which air is drawn, in whichair and fuel are mixed, and from which the mixture of air and gaseousfuel is withdrawn.

A Reference to Figs. 6, 7, 8, l0 and l1 will make clear the constructionand function of the double valve E",

E2 in its relation to the inixing chamber and volatile i liquid supply.The port e is considerably larger than the port e2 and the port e4 isconsiderably larger than the port e3. When the double valve E is closedso as to throttle the supply oi fuel and air mixture to the engine, theseveral ports stand as shown in Fig. Il. The upper valve opening e2,coperating with the adjacent wall of the carbureter casing determines.the minimum cross sectional area of the air inlet passage to thecarburetor, While the valve port e3 of the lower portion E2 determinesthe minimum cross sectional area ofv the mixture outlet through whichmixed air and fuel pass to the engine. These ports are so proportionedthat at the extreme throttling position when a practical minimum ofexplosive mixture is fed to the cylinder, the minimum cross sectionalarca of the mixture'passage is decidedly less than the minimum crosssectional area of the a'ir supply passage; that is to say, the conduitleading from the mixing` chamber of the carbureter is, in effect, muchsmaller than the conduit leading to the mixing chamber. As the throttlevalve E YE2 is opened, Athe ports e2 and e3 coperating with the adjacentportions of 'the carbureter casing afford a larger and larger passagefor the gases inducted into the engine, until in the opening of thethrottle valve the condition shown in Fig. l0 is arrived at When theport openings are all'at their maximum and afford the freest possiblepassage oi gases to the engine. In the position ol valve shown in Fig.l0 the preponderance of minimum cross section oi air inlet over theminimum cross section of mixture outlet has largely disappeared, the twopn" ages being nearly of the same size. As the valve is closed graduallytowards the position shown in Fig. ll, (he effective prcponderanee ofair inlet cross sectional arca over mixture oiulet cross sci-tional areaincreases gradually and progressively.

Th1:I result of he abo ve described arrangement is to maintain in themixing chamber D a substantially constant pneumaiicprl-ssnre. Fora givenengine the Iransniitting capacity ol thc-k .is conduits ol' thecznlnlrctcr is determined with reference to the cylinder space, so thatwith these passages open as Wide as may be, [he

l l l pneumatic lpressure in the mixing chamber of the carbureter issuflieient to insure an effective draft upon the liquid fuel supplyvfrom the float chamber. When this condition of full and free openingisestablished tho problem of adjustment and graduation of conditions toSilit the engine when running under the throttle, remains to beconsidered and solved.. When the engine is running with a full supply ofexplosive mixture, if the relation of effective cross sectional area ofthe liquid iuel passage to the cross sectionaly area of' the air inletbe fixed at say l to 00 and.- atthis ratio the desired proportions ofgaseous ingredients in the explosive mixture are fed to the engine, itwill be mechanically fairly easy to preserve this relationship betweenthe liquid fuel and air inlet areas and-if the draft which determinesthe effect of liquid fuel at the spraying nozzle remain substantiallyconstant, the mixtureproportion will be preserved throughout allpositionsof the throttle valve, or may be accurately and definitelygradedto insure maximum explosive efiiciencynnder all conditions. Theeffect of so proportioning the throttle valve openings that thepreponderance in cross sectional area of the air inlet over the mixtureoutlet increases gradually as the throttle valve is closed is to confinethe extreme variations in pneumatic pressure to those parts of the gaspassages which lie between the mixture outlet'from the carbureter andtheeng-ine cylinders, the relatively large area of the air inlet beingsufficient to supply all the demands for more 'air which can be madeupon it by the restricted area of the outlet without decrease ofpneumatic pressure in the mixing chamber.

I have determined by experiments and practice that a ratio of air inletarea to mixture outlet area of 4 to l at the extreme throttling positionof the valve Will insure the maintenance of the same pneumatic pressurein the mixing chamber as an area ra! io of about 6 to 5 with thethrottle yalve wide open, and that by gradu- :iting this ratio Vfrom oneextreme to the other steadily as the throttle valve is closed, preservesthe pneumatic,y pressure in the mixing chamber substantially constantunderall conditions. Having by this means secured a constant-vacuumdraft upon the liquid fuel spray nozzle under all of the conditions o1'throttle valve opening, I am enabled to maintain the same proportions offuel to air in the combustible mixture Whether the throttle valve beopened or closed. if, for instance, it be determined that thepropermixture would be obtained by having' the liquid fuel valve openingone four-hundredth part of the area of the air inlet opening when thethrottle valve is Wide open, this proportion may be preserved by somounting and controlling the liquid valve that it shall close anddiminish thearea of the liquid opening in constant proportion to thediminution of the air supply opening. On the other hand. if it bedesired to make a progressive change in the fuel value of the mixture asthe total quantity thereof admitted to the engine is reduced, the partsto which the liquid 'valve is secured may be so proportioned that theliquid valve while openzling to close or open by even graduations shallgradually bange the proportion between liquid adn ion waive urea and airadmission areaA Indeed it is usually desirable to multe :auch pro;2.tsively gradu- .ated differences in the speciiciuelvalue of themixture-'asthe engine vis throttled for .the reason thatthe proportionof combustion-products containedinthe cylinder`clearancesbecomesgreaterasthc throttle valve is closed', and t`o"c )mpensatev fortheincreased'proportion` of the combustionproducts itis well to increasethe i specic fuel value of the mixture entrained to the sylinl der. .Theform of mechanism illustrated in the drawings which accomplishes thisresult is shown irl Figs. 2, 3' and 9. The' valve Bs is mounted' uponthe`screw threaded stemjB, 'The cap B is fastened rigidly to .the'top ofvthe'sziidI screw-stem and confines the spring b6 whichl -the mixed gaseslfrom the carburetertothe engine.l

seats in the`ca`p B' and upon the top-of thefstandard b4, The arm Bextends from the .cap 'Bi and ca iries uponits outer end the pinb whichenters a' hole made for the purpose in the end of the arni B7.' :Thisarm B'V is sleeved to turn upon -tlie standard bfand below it,` likewise'sleeved upon'the saidSstandard, there is placed 'the'crank Bs.- Anextension' Blo of the arm B1l is slotted as shown in'Fig. 2 andthe screwbl which .is threaded into 'the crank arm B's passes through this slot-a'nd secures-the crank'Band arm-"i310 in any desred position orrelation within the scope Oiadjust- 'mentl permitted by' this slot-intheextension Bm.

'- 25 The outerend of the crank Bf is provided with a hole whichadmitsthe pin E -in one en d of the' link E, the other end of said linkbeing similarly pinned to thel crank E." Thus as the crankE is 'operatedto open or close the'double throttle valve E E?, by means of theconnections through link E, crank Bs, armsB and B the screw threadedvstem B4 turned'v and the valve` B3 4openedor closed. I t will'mow'lieperceived that by-determining thepitch of the thread'of the screw B*onmay also deterr'ninethe rate o`i change in the 'ratio between the fuelinletlopenipg fand theair inlet opening.4 Ihaveiound in practice, forinstance, that "a proportion of fuel inlet are'a to air inle'tarea of lto l 400 yields admirable results when the engine 4is' run;y ning'atfull power and the throttle valve isnor em- 40 ployed to restrictthe airsupply, butlhat the same engine will run with-.best economy whenthrottled tothe extreme point if this ratiobe then changed to about 1 to350. If, therefore,- a given pitch of'the screwB had been calculatedandasccrtained to pre- '45 serve this ratiol without variation,"the-'provision of a screvvf'-oil slightly greater pitch will cause theratio to vary a's-desired and above suggested.

In order to adjust the initialopening of the liquid fuel valve, I'haveprovided the devices hereinbefore` alluded to, namely, the quadrantslotat Bl in the arm B7 and the adjusting screw bl". 'By slackening thisscrew blo the valve s'tem'Bf may b e turned within the limits of theslot and the initial opening of the valve varied to suit/the conditions,the parts being set by turning down the screw bw.' The oflice'of thespring b (see Fig. 3) is to take up all back lash and hold the valvestem firmly toits bearing.

'lhe spray nozzle formed, in the specific instance illustrated in thedrawings, by the perforation D in the bridge D and the stem head D, isdirected downward; this arrangement in my estimation being superior iuits eli'ect to one wherein the spray nozzle delivers its contentsupward. The assemblage oi the parts is made -easy by'securing or formingthe s tem D5 upon the screw threaded-cap D'* which maybe =in 65 sertcd4from above the stem D5 .and -passed into` 'the aperture 'D3 .so thatvythe head D forins aisuitable annular spray 'nozzle in copenitionfv'iiththe sides of the vertical aperture. v 1

In order to effect' a thorough intermiirture of the 70 volatilized fueland the ain -I orinfthe mirringcham'f ber casing so as to" provideataperingand preferably conical cinnbiningti1be D12 immediately below thespray nozzle; This tapered combinngfiube, which should be concentic withth'e spray nozzle axis,ma 7 terially assists in preservingasteadyentiainment of The throw of the throttle valve and-thearticulately connectedfuel valve may be suitably adjusted by the screwf3 set in the block or standard E3`- so as to make 8 0 contactalternately with the crank arrnE* or the ear E?.

1 'In u'carbureter, a gas .conduit comprising an.air inlet mixingchamber and mxturefoutictQ'aQ spray nozzle, a limsi fuel passage to thespray nozzle, a' fuel valve, 85 and throttle valves lcontrolling the-alr inlet and mixture. outlet, respectively, 'and means to opemaudjclose the two throttle valves and the fuelivalve simultaneously, andmeans to increase 'gradually the 'ratio' ofuel valve lopening 'toali-.valve opening'f-as the air valve opening 90 decreases. f 2. in ncarb'ureter, a gas-conduit c ornprlsingralxA air inlet mixing chamberand mixture outlet, s. spray nozzle,

a liquid fuel passage to the spray nozzle, a: fuel. v alve, und throttlevalves controlling the air inlet .s.'id mixture 95 outlet. respectively,and 'in eans to open ggnq'fclo'se the two throttle valves and the fuelvalve simultaneously, the effective sectlopal area ot the airduiet beinggreaterA at all normal working positions of the throttle valves -tlmn'the effective sectional area ot` theinlxture' outlet, 100 I and meansto. increase gradually the ratio o! fuel valve opening to air valveopening as the air valve'openlng decreases.

il. In n carbureter, a gas conduit comprising an air inlet mixingchamber and mixture outlet, a spray nozzle, .a liquid iucl passage tothe spray nozzle, andI throttle effective v'nlve port area of the inletthan of the outlet, 11 0 ut all normal working positions' ot the'valves, and to -licei-ease the proportionate preponderance ot inlet overoutlet asboth increase.

4. In a carbureter, a gas ,conduit comprising an air inlet mixingchamber and mixture outlet, a spraynozzle 1.1 5`

a llq'lxid-tuel passage t6 the spray-nozzle, a lfuel-valve; throttlevalves. to control the air inlet and mixture outlet.. respectively,means to open andrrclose the two throttle valves und the fuel' valvesimultaneously, the etl'ec-tvc sectional n'rea ot the air inletgreaterat all normal work- 120 ingposltlons of the throttle -vlves thanthe ehectlvesewtional areo.- ot the mixture outlet, the throttle'valvesproportioned to decrease the proportionate propenderanco oi1 inlet arcaover outlet area as both increase, and' menus. to increase gradually theratio of fue! vulve onaning -toali' valve opening as the air valveopening decreases,

il. in a carburetor, a misc-enduit comprising n mixing chamber,v un airinlet communicating with', the upper end thereof. and a mixture outletcommunicating with the lower cud. :i liquid fuel pipe bridging thc gasconduit nbovc the mixing chamber, an aperture. insulti liquid fuel pipoand a spray' nozzle in -said aperture. directed downward toward themixing chamber.

6. ln n carburetor. the combination of a liquid [nel valve'. u conduit'wutrollcd thereby. a vertical tubular 135 mixing chamber, n n nir inicito thc top thcrcot und. a mixture' outlet from thc-'bottom thereof. :lhorizontal tube extending 'into tbc mixing chamber midway between theair iu'let :and mixture outlet, the bore of said tube 'communicatingwith 4th v alve controlled Vliquid fuel conduit, s aid tubealsotransversely -and vertlcally perforated,

' to admit' the 'insertion of '-a. spraying device from the Sop.thm-enf, 'aud the spraying .devicel to deliver .fuel in a Adowziwardspray intothe mixing chamber.

7. In u carbureterfthe combination ot' fuel conduit.'

au airinlet; a mixiug' ':hamber, mixture outiet, a throttle valvehsvinggportu 'to control, both the -air inlet aud mix'tu'reoutiet,`meangytn 'open'nd"close said' ports vsimulta' neously, the elective areaof the air' inlet being greater thairthatf the lnlx'tur outlet at gliworking' positions of `the'valve;'dsprey'uozzieito delive;Y fuel tothe.mixiug vclose them simultaneously and to maintin u predetermined rateo!change in the ratio between the effective 'port areals of the tuelvalveaud air waive..

-Signed b y me at Boston, iiassachu'setps, this sixteenth .'day ofFebruary, 1906. Y

